Design And Optimization Of A High Throughput Chemical Vapor Deposition System For Depositing Thin Films Of Iron Pyrite For Photovoltaic Applications

Iron pyrite (FeS2) is a promising material to act as the light absorbing layer in a thin film solar cell. This thesis focuses on the design and optimization of a chemical vapor deposition (CVD) chamber capable of depositing iron pyrite thin films by the reaction of iron acetylacetoneate and tert-butyl disulphide in argon at 300 oC at a base pressure ranging from 10 mTorr to 760 Torr. A custom, as-built 5" CVD system is first characterized by performing experiments attempting to deposit thin films of iron pyrite at a base pressure of 10 mTorr. After initial efforts are unsuccessful, a series of modifications are made to the system, and experiments at both low and atmospheric pressure are pursued. It is found that an external chamber for the iron acetylacetoneate precursor is necessary for better control over its vapor pressure, and that the growth rate must be slow to deposit homogeneous films. Optimal results at atmospheric pressure are achieved when the flow lines of the TBDS vapor, iron acetylacetoneate vapor, and argon carrier gas are combined prior to the deposition chamber.

Pursuing a scalable production methodology for materials and advancing it from the laboratory to industry is beneficial to novel daily-life applications. From this perspective, chemical vapor deposition (CVD) offers a compromise between efficiency, controllability, tunability and excellent run-to-run repeatability in the coverage of monolayers on substrates. Hence, CVD meets all of the requirements for industrialization in basically all areas, including polymer coatings, metals, water-filtration systems, solar cells and so on. The Special Issue “Advances in Chemical Vapor Deposition” is dedicated to providing an overview of the latest experimental findings and identifying the growth parameters and characteristics of perovskites, TiO2, Al2O3, VO2 and V2O5 with desired qualities for potentially useful devices.

"Chemical Vapour Deposition: An Integrated Engineering Design for Advanced Materials" focuses on the application of this technology to engineering coatings and, in particular, to the manufacture of high performance materials, such as fibre reinforced ceramic composite materials, for structural applications at high temperatures. This book aims to provide a thorough exploration of the design and applications of advanced materials, and their manufacture in engineering. From physical fundamentals and principles, to optimization of processing parameters and other current practices, this book is designed to guide readers through the development of both high performance materials and the design of CVD systems to manufacture such materials. "Chemical Vapour Deposition: An Integrated Engineering Design for Advanced Materials" introduces integrated design and manufacture of advanced materials to researchers, industrial practitioners, postgraduates and senior undergraduate students.

Chemical Vapor Deposition Polymerization - The Growth and Properties of Parylene Thin Films is intended to be valuable to both users and researchers of parylene thin films. It should be particularly useful for those setting up and characterizing their first research deposition system. It provides a good picture of the deposition process and equipment, as well as information on system-to-system variations that is important to consider when designing a deposition system or making modifications to an existing one. Also included are methods to characterizae a deposition system's pumping properties as well as monitor the deposition process via mass spectrometry. There are many references that will lead the reader to further information on the topic being discussed. This text should serve as a useful reference source and handbook for scientists and engineers interested in depositing high quality parylene thin films.

Handbook of Chemical Vapor Deposition: Principles, Technology and Applications provides information pertinent to the fundamental aspects of chemical vapor deposition. This book discusses the applications of chemical vapor deposition, which is a relatively flexible technology that can accommodate many variations. Organized into 12 chapters, this book begins with an overview of the theoretical examination of the chemical vapor deposition process. This text then describes the major chemical reactions and reviews the chemical vapor deposition systems and equipment used in research and production. Other chapters consider the materials deposited by chemical vapor deposition. This book discusses as well the potential applications of chemical vapor deposition in semiconductors and electronics. The final chapter deals with ion implantation as a major process in the fabrication of semiconductors. This book is a valuable resource for scientists, engineers, and students. Production and marketing managers and suppliers of equipment, materials, and services will also find this book useful.

Iron pyrite (FeS2) is a promising earth abundant semiconductor for applications in thin film photovoltaics. This thesis focuses on the growth and characterization of pyrite thin films and single crystals. Single phase, large grain, and uniform polycrystalline pyrite thin films are fabricated on glass and molybdenum coated glass substrates by atmospheric-pressure chemical vapor deposition using the reaction of iron (III) acetylacetonate and tert-butyl disulfide in argon at 300°C, followed by sulfur annealing at 500-550°C to convert marcasite impurities to pyrite. Large, pure phase, and high quality pyrite single crystals were grown using a Na2S based flux growth technique. Thin films and single crystals were characterized by numerous techniques including X-ray diffraction, Raman spectroscopy and Hall effect measurements. The films exhibit low mobility, high carrier concentration p-type behavior while the single crystals exhibit high mobility, low carrier concentration n-type behavior, consistent with literature. The temperature dependence of the hall coefficient of single crystals shows the first clear transition from n-type behavior at room temperature to p-type behavior at low temperatures in pyrite. In addition, simple polishing of the surface is shown to modify the concentration of holes, demonstrating that p-type carriers can originate from the surface of a high quality pyrite single crystal.

This volume provides the first comprehensive look at a pivotal new technology in integrated circuit fabrication. For some time researchers have sought alternate processes for interconnecting the millions of transistors on each chip because conventional physical vapor deposition can no longer meet the specifications of today's complex integrated circuits. Out of this research, ionized physical vapor deposition has emerged as a premier technology for the deposition of thin metal films that form the dense interconnect wiring on state-of-the-art microprocessors and memory chips. For the first time, the most recent developments in thin film deposition using ionized physical vapor deposition (I-PVD) are presented in a single coherent source. Readers will find detailed descriptions of relevant plasma source technology, specific deposition systems, and process recipes. The tools and processes covered include DC hollow cathode magnetrons, RF inductively coupled plasmas, and microwave plasmas that are used for depositing technologically important materials such as copper, tantalum, titanium, TiN, and aluminum. In addition, this volume describes the important physical processes that occur in I-PVD in a simple and concise way. The physical descriptions are followed by experimentally-verified numerical models that provide in-depth insight into the design and operation I-PVD tools. Practicing process engineers, research and development scientists, and students will find that this book's integration of tool design, process development, and fundamental physical models make it an indispensable reference. Key Features: The first comprehensive volume on ionized physical vapor deposition Combines tool design, process development, and fundamental physical understanding to form a complete picture of I-PVD Emphasizes practical applications in the area of IC fabrication and interconnect technology Serves as a guide to select the most appropriate technology for any deposition application *This single source saves time and effort by including comprehensive information at one's finger tips *The integration of tool design, process development, and fundamental physics allows the reader to quickly understand all of the issues important to I-PVD *The numerous practical applications assist the working engineer to select and refine thin film processes

A laboratory-scale reactor and a novel method for the atmospheric pressure chemical vapor deposition (APCVD) of SiO2-x films are developed. The deposited films are investigated to synthesize heterogeneously upon the substrate surface with the elimination of the so-called gas-phase reaction, hence preventing parasitic oxide particles upon the substrate surface and the reactor inner walls. The films are extensively inspected in terms of chemical and optical properties and utilized for crystalline silicon solar cell applications. Simple reactor design with low safety measures, a wide range of deposition rates, high film resilience, and stability for the intended applications are successfully achieved. The newly developed APCVD SiO2-x is proven to protect the Si wafer surface against texturing in alkaline and acidic solutions. Electroplated metallization schemes of heterojunction and passivated emitter rear contact solar cells are examined with the use of the SiO2-x as a masking layer in the grid electrode-free area.